Advocating for Drawdowns

By changing the way dams are operated, we can mimic natural water levels on the Upper Mississippi River.

Bald Eagles benefit from vegetation that sprouts along the Mississippi River when water levels are temporarily drawn down. Photo: Terri Shaddick, Audubon Photography Awards

The natural pattern of water levels on the Upper Mississippi River included a spring flood followed by low water levels during summer. For centuries this pattern created ideal habitat for hundreds of species of migratory and resident birds, including tundra swans, bald eagles, and spotted sandpipers.

When locks and dams were constructed during the 1930’s, they changed this pattern and eliminated the natural low water conditions. Over time this has resulted in declines in aquatic vegetation, and many areas have converted to more turbid, open water conditions with poor habitat for fish and wildlife. Fortunately, we can restore some of the natural low water conditions by conducting summer, pool-scale drawdowns. We are working to accomplish these by changing the way the dams are operated.

What is Audubon doing and how can you help:

•We are working closely with the Corps of Engineers and other partners to conduct summer drawdowns on individual pools and have been successful in Pools 5, 6, and 8 – with your help we can continue to advocate for additional pool drawdowns.

•We are evaluating the feasibility and cost of changing the operating plan for Lock and Dam #8 near La Crosse to make drawdowns a routine part of dam operations – with your help we can cost share the feasibility study and conduct the additional one-time dredging needed to establish a new operating plan, and set a precedent to include more pools in the future.